Electric heater for outdoor use



E. A. EVERETT. ELECTRIC HEATER FOR OUTDOOR USE.

APPLICATION HLED MAR. 13. 1919.

Patented Feb. 28, 1922.

UNITED STATES PATENT OFFICE.

EDWARD A. EVERETT, OF NEW YORK, N. Y., ASSIGNOR TO Q dc C COMPANY, OFNEW YORK, N. Y., A CORPORATION OF MAINE.

ELECTRIC HEATER FOR OUTDOOR USE.

Application filed March 13, 1919.

To all whom it may concern:

Be it known that I, Enwann A. Evnnn'r'r, a citizen of the United States,and resident or" New York, in the county of New York and State of NewYork, have invented cer tain new and useful Improvements in ElectricHeaters for Outdoor Use, of which the ,t'ollowing is a specification.

This invention relates to electric heaters and has for an objectproviding a heater suitable for out-door service that is rugged, thatcan stand excessive vibration and knocks such as would be encountered ona railroad track and that is effective when immersed in water. In theaccompanying drawings forming part of this specification, Fig. 1, showsa heater unit complete, Fig. 2, is a sectional elevation with )art ofthe coil, however, shown complete, *ig. 8 is a crosssection on line o-bof Fig. 2; Fig. at is a section of the safety valve and Figs. 5 and 6show the application of the heater units to a railroad switch.

11 represents a length of wrought iron pipe to which the reducing caps12 and 13 are screwed. Into the cap 12 the pipe l l is screwed and intothe cap 13 the pipe 15 carrying the valve 16 is screwed, however thisvalve may be screwed directly into cap 13. Pipe 29 is screwed into cap12 and extends within pipe 11 between caps 12 and 13. This pipe iscovered with a layer of asbestos cloth 28, Fig. 3 which is a nonconductor of heat and also forms a cushion to take up small vibrationsfrom the outer covering and heating coil. The outer covering 27 consistsof a cement applied in a plastic form and which tends to harden underheat. The heating coil consists of a spiral of high resistance wire 23such as is commonly used in electric heaters. This coil is partiallyembedded in the cement 27 which holds it in place. Two straps 26 areprovided for clamping the asbestos cloth to pipe 29 and terminals 24.-and 25 may be secured to these straps for terminating the ends of theheating coil as shown in Fig. 2.

The conductors 21 and 22 are connected with a source of electric supply.These are led into the heating coil through the pipe let where theyconnect to asbestos covered wires leading to the terminals 24: and 25.In pipe 29 and in that portion of pipe 14 Specification of LettersPatent.

Patented Feb. 28, 1922.

Serial No. 282,423.

subject to heat a filling 31 of mineral wool is provided surrounding theconductors which holds them in place and absorbs vibration. Adjoiningthe mineral wool, a section of pipe 14: is filled with sealing war; asat 32, F 2, this forms a long waterproof seal for the outlet of theconductors. The outer end of the pipe 14 is filled with a cement 33which hardens and forms a mechanical protection to the other fillings.The pipe 14 forms a convenient handle by which the units may be carriedeven when they are heated.

l/Vhen the chamber enclosed by pipe 11 is heated, the air and othergases in it are heated and expand, to permit these gases to escape thesafety valve 16 is provided. This consists of a plunger with a valveseat 42, Fig. 4, held closed by the spring 41. When the pressure underthe valve overcomes the spring the gases escape through the filter 43;this filter is provided to pre vent dust from getting to the valvemechanism.

One use to which this invention is particularly adapted is for thawingswitches on a railroad track. For this purpose the units are placedbelow the rails 17 and 18 as shown in Figs. 5 and 6. In this position,vibration is excessive and the outer shell must be able to resist blowsfrom falling objects on passing trains. This construction is strong,comparatively light and the walls of the shell are thin to radiate theheat. The radiating surface is so designed with relation to the heatingcapacity that while it will melt snow and ice, it will not boil water.

Having thus described my invention, I claim:

1. In an electric heater of the class described, in combination, alength of iron pipe of large diameter, reducing caps screwed to each endof said pipe, a length of pipe of small diameter screwed to one of saidcaps, a heating coil enclosed within said large diameter pipe,conductors to said heating coil inserted within said small diameterpipe, and said latter pipe being filled with mineral wool where it issubject to heat. with a WZLtBDPIOOf sealing compound adjacent to saidmineral wool and with cement at the outer end.

2. In an electric heater of the class described, in combination, alength of pipe of ing coil led out through said exterior length largediameter, reducing caps screwed to of pipe.

each end of said pipe, an exterior length Signed at New York in thecounty of of pipe of small diameter screwed to one New York and State ofNew York this 5 of said caps, an interior length of pipe of third day ofMarch A. D. 1919.

small diameter extending between said caps a covering of asbestos clothfor said eXtBllOl EDWARD A. EVERETT.

ipe, a covering of cement over said asbestos Witnesses: cloth, a heatingcoil partially embedded i; SUE SEGAL, 10 said cement, and conductors forsaid heat- SYLVIA HAHN.

